Professional Comparison of Martensitic Stainless Steel Tube: 410, 420, and 440 Series

In the field of industrial metal piping, Martensitic Stainless Steel Tube occupies a core position in application scenarios requiring high strength and hardness due to its unique heat-treatable strengthening characteristics. However, when faced with 410, 420, and 440 series, many engineers and buyers find it difficult to balance corrosion resistance with mechanical performance.

This article details the differences between these three mainstream martensitic stainless steel tubes from the perspectives of chemical composition, mechanical properties, and typical application scenarios.

Chemical Composition: The Balance of Carbon and Chromium

The performance core of Martensitic Stainless Steel lies in the ratio of Carbon and Chromium.

410 Series: As the basic grade of the martensitic family, its Carbon content is low (approximately 0.08%-0.15%), and Chromium content is between 11.5%-13.5%. This provides it with good toughness and fundamental corrosion resistance.

420 Series: Known as "Cutting Tool Grade" stainless steel, its Carbon content increases to 0.15%-0.40% or higher. Higher carbon content allows it to achieve significant hardness improvements after heat treatment.

440 Series (Especially 440C): Belonging to high-carbon high-chromium stainless steel, the Carbon content is as high as 0.95%-1.20%, and Chromium is increased to 16%-18%. It is the hardest among all stainless steel types.

Mechanical Properties: Hardness, Strength, and Brittleness

Through Heat Treatment, these three materials exhibit distinctly different mechanical behaviors:

410 Series: Balance of Strength and Processability

410 Martensitic Stainless Steel Tube has good processing performance in the annealed state. After quenching, its hardness is usually around 35-45 HRC. It provides moderate tensile strength and excellent fatigue resistance, suitable for structural parts that bear loads but do not have extremely high wear resistance requirements.

420 Series: Excellent Wear Resistance

After quenching and tempering, 420 series tubes can reach a hardness of over 50 HRC. Due to the dispersed distribution of carbides in the matrix, its wear resistance far exceeds the 410 series. However, in a high-hardness state, its Ductility and impact toughness will decrease.

440 Series: Representative of Extreme Hardness

The 440C series is the "ceiling" of hardness, with hardness reaching 58-60 HRC after quenching. Pipe fittings made of this material have extremely high compressive strength and deformation resistance, but they are also the most brittle and are generally not recommended for components subjected to severe impact.

Corrosion Resistance Comparison: Surface Protection

Although the corrosion resistance of Martensitic Stainless Steel is generally lower than that of austenite (such as 304/316), there are still levels among the three:

410: Provides basic resistance to atmospheric corrosion, water vapor, and fresh water corrosion.

420: After complete quenching and polishing, its corrosion resistance reaches the best state, resisting food acids, mild alkalis, and atmospheric environments.

440: Thanks to higher Chromium content, it possesses the strongest oxidation and corrosion resistance among martensitic steels under hardened conditions, even resisting some chemical media.

Industrial Application Scenarios

410 Martensitic Stainless Steel Tube: Widely used for pump parts, valve bodies, and bolts in the oil and gas industry, as well as wear-resistant mechanical structural pipes.

420 Martensitic Stainless Steel Tube: Commonly used in medical devices (such as surgical tool handles), high-precision shaft sleeves, pressure vessel accessories, and the mold industry.

440 Martensitic Stainless Steel Tube: Primarily targeted at aerospace bearings, high-load nozzles, valve seats, and industrial precision bushings requiring extremely high hardness.

2026 Industry Trends

As global manufacturing shifts toward precision and low-carbonization, the Martensitic Stainless Steel industry is embracing three major trends:

Rise of Super Martensitic Steel: By maintaining ultra-low carbon content and adding Nickel and Molybdenum, new materials with better welding performance and stronger resistance to acidic environments are being developed. They are replacing expensive duplex steels on a large scale in deep-sea oil and gas field development.

Deep Integration of Surface Treatment Technology: Utilizing Plasma Nitriding or PVD coating technology further improves the erosion resistance of martensitic stainless steel tubes without changing the matrix hardness, extending service life in harsh working conditions.

Digital Heat Treatment Control: In 2026, AI-driven induction quenching technology will achieve precise prediction of tube metallographic structures, significantly reducing residual Austenite and improving the dimensional stability of pipe fittings, which is crucial for the high-precision machinery market.